

type p1 = keyof {
    name: string;
    age: number;
}; //'name' | 'age'
  
  // type p2 = Person[keyof Person]
  
  let str: (a: any, b?: string[]) => boolean;

  str = (a: any, b?: string[]) : boolean =>  {
      console.log('a', a);
      console.log('b', b)
    return true;
  }

  str('a', ['1'])
  